The former Maricopa County sheriff told the Washington Examiner he's upset at negative reaction to the Friday pardon, and that he feels Republican politicians are insufficiently supportive of the president, who he calls a great man.

"I could run for mayor, I could run for legislator, I could run for Senate," Arpaio said Monday. One particular race, however, is likely to gain significant attention: the GOP primary next year facing Flake, R-Ariz., a forceful Trump critic.

"I'm sure getting a lot of people around the state asking me" to challenge Flake, said Arpaio, who served 24 years as sheriff before losing reelection in 2016. "All I'm saying is the door is open and we'll see what happens. I've got support. I know what support I have."

Arpaio said he swore off another candidacy in January, when he left office, but that "with what I've seen happening in recent months, especially what's happening with our president, I said, 'Hey, why not?'"